This is where treasure was kept. Small fish and meagres are found here. The first time through, it will be locked, but divers will notice a hole large enough for Oceane to squeeze through, and she will open the door.

A giant, glorious ballroom where people had danced when the castle was above water, it is still the perfect ballroom for fish to swim in. Coral reef fish, schools of fish and even a false killer whale are found here. A Luna Lionfish gaurds the throne, but can be moved aside by drawing with the underwater pen. Doing this will expose the Glorious Key, which opens the door to the King's Chamber. The Ailouros Pearl can be seen in front of the throne in zoom mode (only after beating the Valka Castle chapter), and the Phantom can be seen here at night (only after beating the main plot). Thanatos can be seen outaide of the windows here as well.

Just outside the ballroom, there is a door that was locked on the other side, but can be opened on the side the diver is currently at.

This is the room where the mighty Prince Valka stayed in. It is opend by using the Glorious Key. It has a portrait of Prince Valka on the wall, which gives a clue about how to open the Secret Room. It also has Anximander's map of the circular earth, which becomes very important in the main storyline. After entering and finding the Secet Room, the doors will close and lock, trapping the diver and Oceane in the chamber after The Song of Dragons is played. The only way out is by having Oceane activate a mechanism under a desk while you push the door open, but it will only work if it is done at the same time. After doing this, a North Atlantic Right Whale can be seen outside the window, but only at that point in the story.

A small room connected to the King's Chamber. It is opend by moving the book entitiled Clavis (key in Latin). There are many Cloudy Catsharks on the floor here, as well as a few savagable items. This is where the first Okeanos Tablet is found.